\begin{figure}[H]
\centering
\begin{subfigure}[b]{.24\textwidth}
\centering
\figscale{
  \begin{tikzpicture}[%
    >=stealth,
    shorten >=1pt,
    node distance=2cm,
    on grid,
    auto,
    state/.append style={minimum size=2em},
    thick,
    scale=0.2
  ]
    \node[state, rectangle, align=center] (N1) {$A$\\$\textcolor{BrickRed}{EX(\textcolor{Blue}{\$B})}$};
    \node[state] (N2) [below left of=N1] {$B$};
    \node[state] (N3) [below right of=N1] {$C$};

\path[->, BrickRed]
	(N1) edge node [above left] {$\textcolor{Blue}{\$B}$} (N2);

\path[->]
	(N1) edge [bend right] node {} (N3)
	(N3) edge node {} (N1);
  \end{tikzpicture}
}
\caption{$EX(\$B)$}
\end{subfigure}
\begin{subfigure}[b]{.24\textwidth}
\centering
\figscale{
  \begin{tikzpicture}[%
    >=stealth,
    shorten >=1pt,
    node distance=2cm,
    on grid,
    auto,
    state/.append style={minimum size=2em},
    thick,
    scale=0.2
  ]
    \node[state, rectangle, align=center] (N1) {$A$\\$\textcolor{BrickRed}{EX(\textcolor{Blue}{true})}$};
    \node[state] (N2) [below left of=N1] {$B$};
    \node[state] (N3) [below right of=N1] {$C$};

\path[->, BrickRed]
	(N1) edge node [above left] {$\textcolor{Blue}{true}$} (N2);

\path[->]
	(N1) edge [bend right] node {} (N3)
	(N3) edge node {} (N1);
  \end{tikzpicture}
}
\caption{$EX(true)$}
\end{subfigure}
\begin{subfigure}[b]{.24\textwidth}
\centering
\figscale{
  \begin{tikzpicture}[%
    >=stealth,
    shorten >=1pt,
    node distance=2cm,
    on grid,
    auto,
    state/.append style={minimum size=2em},
    thick,
    scale=0.2
  ]
    \node[state, rectangle, align=center] (N1) {$A$\\$\textcolor{BrickRed}{EX(\textcolor{Blue}{dead})}$};
    \node[state] (N2) [below left of=N1] {$B$};
    \node[state] (N3) [below right of=N1] {$C$};

\path[->, BrickRed]
	(N1) edge node [above left] {$\textcolor{Blue}{dead}$} (N2);

\path[->]
	(N1) edge [bend right] node {} (N3)
	(N3) edge node {} (N1);
  \end{tikzpicture}
}
\caption{$EX(dead)$}
\end{subfigure}
\begin{subfigure}[b]{.24\textwidth}
\centering
\figscale{
  \begin{tikzpicture}[%
    >=stealth,
    shorten >=1pt,
    node distance=2cm,
    on grid,
    auto,
    state/.append style={minimum size=2em},
    thick,
    scale=0.2
  ]
    \node[state] (N1) {$A$};
    \node[state] (N2) [below left of=N1] {$B$};
    \node[state, rectangle, align=center] (N3) [below right of=N1] {$C$\\$\textcolor{BrickRed}{EX(\textcolor{Blue}{initial})}$};

\path[->, BrickRed]
	(N3) edge node [above right] {$\textcolor{Blue}{initial}$} (N1);

\path[->]
	(N1) edge node {} (N2)
	(N1) edge [bend right] node {} (N3);
  \end{tikzpicture}
}
\caption{$EX(initial)$}
\end{subfigure}
\caption{Affichages au format \texttt{.dot} obtenus pour les preuves atomiques}
\label{fig:PreuveAtomiqueDot}
\end{figure}